Forklifts have long been used in warehouses and yards where inventory items are stored. A forklift usually has a vehicle frame and a fork assembly attached thereto with powered mechanisms to lift and position the fork. Forklifts have allowed efficient use of storage space in allowing stacking of fairly heavy objects on a minimum of floor space. This has allowed construction of warehouses with relatively small floor space but high storage capacity, thus keeping construction costs to a minimum.
Forklifts have allowed stacking of inventory on top of each other by providing access to the top levels of stacked objects. The fork on the forklift is designed to be able to reach heights of 10 or more feet and to reach up to the top and remove those objects quickly. Safety is provided, both for the person retrieving the objects and for the objects themselves.
The forklift usually has at least two fork tines which make up a fork which is slipped underneath objects which are stacked. The fork is then lifted to pick up the object. However, the fork must be positioned underneath the object to be able to lift it. This usually involves slipping the fork between successive stack layers.
Many different types of pallets have been designed for separating the layers of stacked inventory. The pallets often serve as both a support for the object and as a means for separating one layer of objects from the next thereby providing a space into which the fork may be inserted for picking up each layer. Conventional pallets are usually made of wood. These pallets are relatively expensive, heavy, take up space which could otherwise be used for storage, and are unwieldy to handle when the supported objects are removed.
An alternative pallet has been developed, called the SKEE pallet, made by Elberta Crate and Box, of Dundee, Illinois. SKEE pallets are typically made of flat paperboard and are similar to slip sheets. SKEE pallets, however, have one curved edge so that the pallet looks like a ski in profile. Two of these are usually used between layers of inventory with the curved tips pointing away from one another. This permits the fork of a forklift to slip between the SKEE pallets while minimizing the vertical space taken up by the pallets. This design provides features of low cost, space saving size and shape, and light weight. In particular, the SKEE pallets are far easier to manipulate in many circumstances but suffer from a substantial disadvantage: inserting the fork between stacked layers is far more difficult than with the wooden pallets.
Inserting the fork between SKEE pallets requires far greater care and precision than with wooden pallets. The fork tines are often tapered and polished, and may be lubricated. The fork must be positioned properly both with respect to height and, very importantly, with respect to the tilt angle of the fork so that it properly slips between the two SKEE pallets separating the stacked inventory. However, when the fork insertion is improperly performed, significant damage may occur to the pallets and to the stacked inventory if the tip of a tine pierces the pallet and engages the inventory.